unit a review

UNIT A REVIEWThis is what WILL be on the test!

35 MULTIPLE CHOICE QUESTIONS You should know several examples of biotic &

abiotic factors in the environment.

Abiotic means non-living.

Biotic means living.

Hands up… what are a few examples of each?

Abiotic… temperature, rain, rocks, wind, soil, water, etc.

Biotic… bacteria, flowers, birds, dogs, etc.

KNOW THE DEFINITION OF “SPECIES” Hands up… what is the definition of

species??!!

A group of organisms that can interbreed and produce offspring.

KNOW THE DEFINITION OF AN ECOSYSTEM Hands up… What is the definition of an

ecosystem?

Living organisms interacting with each other and their nonliving environment make up an ecosystem.

KNOW THE DEFINITION OF COMMUNITY Hands up…

All the different species living together in a certain area make up a community.

Remember… all the SAME species in an area are called a populations.

KNOW THE DEFINITION OF A SYMBIOTIC RELATIONSHIP IN WHICH BOTH ORGANISMS BENEFIT… Hands up…

Commensalism- two organisms that live together for mutual benefit are said to be in a symbiotic relationship called commensalism.

A mosquito that bites your arm and sucks your blood is an example of a….?

Parasitic relationship

REMEMBER… All living things need water, nutrients &

energy!

REMEMBER… Plants are producers.

Consumers eat producers.

There must be a lot more producers in an ecosystem to supply consumers.

PHOTOSYNTHESIS Light energy + Carbon dioxide + water =

Food +Oxygen (sugars & starches)

Light from the sun (solar energy) drives the photosynthetic process.

REVIEW PHOTOSYNTHESIS IN YOUR TEXT, PAGES 29 & 30!!

Decomposers: bring about the decay of dead organisms. Decomposers break down EVERYTHING in an ecosystem once it dies. They break down every once living thing.

Scavengers: feed off the remains of living things that are killed by other consumers.

ENERGY USUALLY MOVES THROUGH AN ECOSYSTEM IN THIS ORDER… Solar (sun) producer herbivore

carnivore

An animal that is hunted by other animals is best known as the prey.

Competition is when different species compete for the same limited resource (such as food). For example, hawks, owls, foxes and snakes all eat mice and compete or the limited number of mice available to eat.

AS YOU MOVE UP A FOOD CHAIN, LESS ENERGY IS AVAILABLE. Remember that approximately 90% of energy

is used up at each step, leaving only 10% available to the next step.

Food Webs are a more complex way to represent a feeding system that includes several species of producers and consumers.

THE WATER CYCLE Includes evaporation, condensation, and

precipitation.

When liquid water changes to a gas, it is called evaporation.

SECONDARY SUCCESSION Occurs when a community has been

destroyed or disrupted by a natural event or human activity.

For example… if fire destroyed a section of established forest.

BIOINVASION This is when a non-native species is

introduced into an ecosystem and competes with, or even makes extinct the native species.

For example, Europeans brought cattle and horses to North America which competed Bison over limited grazing resources.

Rats, cats, pigs and dogs led to the extinction of the Dodo bird.

BIOMAGNIFICATION Is the increase in concentration of a

substance that occurs in a food chain.

For example… the build up of a toxin (poison) such as DDT in a food chain.

DDT was used as an agricultural insecticide and has been found to cause cancer, and other problems in organisms.

EXTINCT A species that no longer exists anywhere.

The Dodo bird is an extinct species… can you think of any others?

CLIMAX COMMUNITY Is the final stage of succession.

Succession in nature follows this path:

Primary pioneer secondary climax

THE DESTRUCTION OF AN ECOSYSTEM In any ecosystem, there exists a balance

between all of the populations. At any moment this balance can be disrupted and result in the destruction of an ecosystem.

Remember some of the human causes of destruction and disruptions to ecosystems that we talked about…

GLOBAL WARMING Issues of concern to our communities…

Ultraviolet light is prevented from reaching the Earth’s surface by being absorbed by the ozone layer.

The ozone layer is thinning due to human actions and this is leading to more ultraviolet light reaching the Earth’s surface and causing temperature increases.

Climate change, disease, and pollution has led to the decline of many species, in particular, sensitive tropical species.

(Remember the greatest biodiversity and number of species is found in tropical areas)

USE OF THE LAND… Humans are taking much of many species

habitat over for human needs: food production, housing, the search for natural resources such as oil and gas, and even recreation.

Humans are trying to come up with solutions to some of these problems… remember that we discussed how Parks Canada has developed overpasses and underpasses in Banff National Park to allow for the free movement of wildlife?

This is because roads have cut off many wildlife corridors resulting in disrupted migration patterns and deaths on Alberta highways (mainly of wildlife, but also human deaths).

ECOLOGISTS Are scientists who study relationships of living

things to one another and to their environment.

They often use population sampling to save money, save time, and to get an accurate estimation of a certain population in an ecosystem.

A sample is a portion, piece, or segment that is representative of a whole. So… ecologists might study a portion of the grizzly population in Jasper National Park, not EVERY grizzly bear in the park to learn about the population of grizzly bears.

AN ECOLOGICAL FOOTPRINT shows us what impact our lifestyle has on

Earth’s ecology – including: food, housing, transportation, consumer products and services.

Citizens in developed nations, such as Canada, have bigger footprints than in developing nations, such as Africa because we have and use more resources.

For homework… research the average ecological footprint of people who live in Canada. This will be on the test.

You can calculate your own ecological footprint at:

http://www.myfootprint.org/